Seven weeks into the do-or-die tests that are the "American Idol" live shows, our singing students might finally be getting the hang of things. That's quite a change from week one, when MTV News wanted to hand nearly all of the contestants a failing grade and shove off for an early summer break.

But we stuck around the classroom, and Tuesday night's John Lennon/Paul McCartney-themed show might have offered the most consistent group of performances this season. Special gold stars go to Crystal Bowersox's didgeridoo and Lee Dewyze's bagpipes, both of which added an unexpected world music flavor that had heretofore been missing from the "Idol" curriculum. That's not to say everyone aced the evening. Mr. Aaron Kelly, we're looking in your direction.

So who's standing at the head of the class? Whose grades are slipping? Let's see how everyone measured up with another edition of our "Idol" report card. (And don't miss Jim Cantiello's "Idol" recap in the MTV Newsroom.

Excellent

Casey James: Up until Tuesday night, the 27-year-old's finest performance of the season was his stripped-down, dude-on-a-stool rendition of Bryan Adams' "Heaven." After a few weeks of going the electrified rock-star route, James returned to what worked best for him. During his growly, acoustic take on Lennon's "Jealous Guy," James managed the neat trick of being both vulnerable and ferocious. We dug what we heard, and hope James doesn't wait another few weeks to do something similar.

Good

Katie Stevens: "Let It Be" is as close to an "Idol" failsafe as there is, and Stevens made good on that potential with some on-point vocals. But others before her on the show — Brooke White and Kris Allen — have killed the song. She merely batted it around a bit, like a kitten in a hot pink Snuggie. Again, it was perfectly lovely, but where does the 17-year-old go from here? Back to the awkward, I'm-a-big-girl-I-swear performances of weeks past? And will she even make it, after two consecutive trips to the bottom three?

Michael Lynche: Big Mike's soul-flecked "Eleanor Rigby" seemed to be the most divisive performance of the evening. Perhaps taking a note from David Cook's 2008 reworking of the same tune, Lynche opted for a daring arrangement that turned the original's string quartet into a beefed-up orchestra. Sure it was a tad theatrical, but it was equally entertaining.

Crystal Bowersox: The only thing that pulled Mama Sox up into this section of the grading curve was that didgeridoo. It certainly wasn't that overstuffed arrangement of "Come Together," which muddled her ever-soulful voice. Still, this is the second straight week that she's stepped outside her Tracy Chapman-esque singer-songwriter comfort zone. She deserves credit for keeping things fresh.

Average

Andrew Garcia: If anyone was hoping Garcia had learned a thing or two after his highly praised performance last week — which came on the heels of several in-over-his-head performances — the first notes of "Can't Buy Me Love" proved otherwise. Call it schlocky, cruise-ship swing. Call it the work of an ear-jangling wedding band that forces you to get drunk just so you can make it to the end of the reception. Just don't call it a comeback, because Garcia has regressed in a serious way. Despite his copious face time on camera since the start of the season, we fear that, with the likes of Paige Miles and Lacey Brown out of the way, Garcia is in trouble this week.

Tim Urban: It's no doubt condescending — not to mention unfair — to judge Urban on a Tim Curve. But that's what Randy Jackson did, and it seems the only way to a) assess the kid without being cruel and b) explain how in the world he's stuck around this long. At least his vocals largely held steady during the performance — a welcome change from previous weeks. Alas, this week will be the same in one key respect: He's headed, once again, into the bottom three. What happens once "Teflon" Tim gets there is anybody's guess.

Siobhan Magnus: She's nothing if not unpredictable. Yet we're beginning to sense a pattern: Magnus hasn't done too well the last week or two. That take on "Across the Universe" sounded like something left on the cutting room floor of Amy Adams' "Enchanted": certainly pleasing to the ear but a tune better kept locked in fantasy land than belted out on the "Idol" stage. It could be a surprise, but Magnus just might be in trouble this week, though her chin-trembling story about her baby sisters may have won her enough votes to avoid the bottom three.

Lee Dewyze: Question! What does it say that the only contestants gifted with an outside-the-box instrument were Dewyze and MamaSox? Were they the only two singers who, coincidentally, thought to haul out oddball instruments on the same night? Or do only producers' darlings get to hire freelance musicians for their performances? Right. In any event, much like Crystal's turn onstage, the only thing memorable about Dewyze's performance was his skirt-wearing bagpiper. His "Hey Jude" was perfectly forgettable ... and it doesn't matter at all! As both producers and voters have decided, Dewyze is a front-runner. He's not going anywhere.

Unsatisfactory

Aaron Kelly: We think it might be time for Kelly to bow out of this "Idol" class and scamper back to the high school from whence he came. Not only was "The Long and Winding Road" the poorest song choice of the night (it's a beautiful tune but one not suited to opening a rockin' live show), but his complete lack of oomph while singing left us so drowsy, we almost didn't make it to the second commercial. Yet we have a feeling none of this matters in the least. Kelly's got a solid fanbase that has never let him fall to the dreaded bottom three. Hard to see how last night's song — no better and no worse than many of his past ones — will change that.

How would you grade last night's "Idol" performances? Give us your report cards in the comments.

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